A sickly childhood led Joseph H. Pilates to pioneer his unique training system, with which he hoped to rid his students of all physical limitations. Inspired by both Eastern and Western philosophies, he combined the mental focus and specific breathing of yoga with the physicality of gymnastics and other sports to create something entirely new.

Lowell Offer was 74 when he went in for surgery to repair a valve in his heart. This kind of operation is no cakewalk, he says--patients typically spend as much as a week in the hospital, and many suffer sternum pain for several months.

Finding an exercise regimen that works for you can become tougher with age. Just ask Lori Black, who knows the challenges many seniors face. She works with them on a daily basis in her yoga classes.